Gate-valve.



COLUMBIA W. C. MARSH.

GATE VALVE.

APFLHIATION flLED JULY 21. I914.

Patented Aug. 10, 1915.

auuemtoz PLANOGRAPH 60.. WA-ININETON. D. c.

WILLIAM C. "MARSH, 0F DUNKIRK,

OF DUNKIRK, NEW YORK, A CORPORATION NEW YORK, ASSIGNOE TO MARSH VALVE COMPANY,

OF NEW YORK.

GATE-VALVE.

Specification of Letters Patent.

Patented Aug. 10, 1915.

Application filed July 27, 1914. Serial No. 853,399.

T all whom it may concern:

Be it known that 1, WILLIAM C. MARSH, a citizen of the United States, residing at Dunkirk, in the county of Chautauqua and State of New York, have invented certain new and useful Improvements in Gate- Valves, of which the following is a specification.

My invention relates to gate valves, and has for its object to provide certain improvements in the construction and operation 0 the same as will be hereinafter more definitely pointed out and claimed, reference being had to the accompanying drawing, in which Figure 1 is a central vertical sectional view of my improved gate valve. Fig. 2 is a detail sectional view of the lifting nut and the closing disks or gates. Fig. 3 is a sectional view taken on the line IIIIII. of Fig. 2. Fig. 4 is a vertical view taken on the line IV -IV of Fig. 2. Fig. 5 is a top plan view of the lifting nut detached.

Similar numerals of reference denote corresponding parts in the several views.

In the said drawing, the reference numeral 1 denotes the body of the valve, the same being provided with the internally threaded inlet aperture 2 and outlet aperture 3, in the usual manner. Removably attached to said body 1 is a bonnet piece 4, the same being retained in position on said body by a threaded ring 5, as shown. Passing centrally through the bonnet piece is the valve stem 6 suitably shaped at its upper end to receive an operating handle, not shown, and reduced in size at its lower end at 7, said valve stem having oppositely pitched screw threads 8 and 9, the screw thread 9 being disposed upon the portion 7 thereof as shown.

Mounted upon the screw threaded portion 9 of the valve stem 6 is a lifting nut 10, the same being internally screw threaded to fit said screw threads 9 and being closed at its lower end as shown. Said lifting nut has formed upon opposite sides thereof the rounded projections 11 for a purpose hereinafter to be described. At its upper end said lifting nut is recessed to receive an annular packing 12, which, when said nut is in its uppermost position, is adapted to contact with an annular seat 13 formed in the bonnet piece 4. Disposed upon opposite sides of the lifting nut 10 are the two closing disks or gates 14 adapted when in their lowermost position to seat against and close the valve seats 15 in the valve body. The lifting nut 10 has formed on its sides near its lower end oppositely projecting lugs 16, the same when the parts are assembled being disposed in recesses 17 formed in the backs of the gates 14 in abutments 18 formed thereon, said lugs 16 at their outer ends being reduce at 19 and lying between upper and lower projections 20 formed on sai abutments, as clearly shown in Figs. 3 and 4. Said projections 19 and 20, when the parts are assembled, are disposed to move vertically in grooves 21 formed in the side walls of the body 1, said parts operating thereby to guide said gates intheir vertical movement and also to retain said gates as well as the lifting nut 10 from rotation.

The closing disks Ll are formed on their innersurfaces with depression." 2: into which extend the projections ll on the lifting nut 10, as shown in Figs. 1, 2 and 3.

In order to rcnuwably retain the packin 12 at the upper end of the lifting nut 10, provide the latter with a. flanged collar 23 adapted to be screwed onto the upper end 0 said lifting nut and to have its flange engage and retain the packing in position.

In operation, when the parts are in the position shown in Fig. 1, the valve is fully opened for the passage of fluid, the gates 14: being elevated by the lifting nut 10, and the packing 12 at the upper end of said lifting nut forced in Contact with the valve seat 13 in the bonnet l, thereby forming a. water tight closure, which, in conjunction with the integrally formed lifting nut 10 having its bottom closed. effectually prevents any leakage around the screw threads 8 and out through the top of the valve. \Vhen it is desired to close the valve, a rotation of the valve stem 6, by reason of the screw threads 8, willcause a bodily downward movement of said stem in the bonnet 4r. carrying with it lifting nut 10, which lifting nut, by reason of the oppositely disposed screw threads 9, receives an additional downward movement, thus providing a quick acting valve. The gates 14, which in their upward move ment, rest upon the projecting lugs 16 of the lifting nut, move downward with said nut, this action being a positive one. due to the contact of said lugs 16 with the bottoms of the recesses 17 in abutmcnts 18, and one which forces said gates 14 positively to their seats. It will be observed in Fig. 1 that the depressions 39 on the gates ll receiving rounded projections ll are flat, thereby permitting vertical play of said projections 11 therein suliicient to cause projecting portions 153 to contact with the bottoms of the recesses 17 without any pressure from said projections on the gates 14, the sole function o said ois-rlions being to form pivots on vvhirh the gates may roeli to provide for perfect seating in the event that the faces of the seats are not machined true. In opening or closing the valve gates i i are prevented from rotation during their vertical unwenirnt by reason of the engagement of their lugs if in the grimve; of the body 1, and the lifting nut ll) also is positively held against rotation by the engagement of its projections 19 in said groove 20, \vl'iereby any binding of said disks by means of strain from the lifting nut in closing said disks eli'eetually is prevented; it being apparent that all side strain or twisting effect which might occur were the lifting nut held against rotation by the disks alone in operating valve, is obviated.

l lav ing thus described my invention, What to secure by Let- I claim as new and desire ters Patent, is:

1. A gate valve, embodying a casing, a St!'0.(-tl13'85iil8(l valve stem therein, closing disks, and a lifting nut supporting said disks and adapted to he raised and lowered by said stem, said lifting nut being closed at its lower end and a hen in its uppermost position being adapted to contact with a valve seat to seal said valve stem against leakage around its threads.

a. gate valve. eiuliinlying a casing, a valve stem in screw-threaded engagement therewith and having its lower end oppositely sci-ew-threaded, a lifting not closed at its lower end and in screw-threaded engagement with .aid lovver end of said stem gates carried in Milli lifting nut, and a. valve seat in said cas ng ahme said lifting not against which a packing in the latter contacts when in its u oii 'iiiost position to seal the valve against leakage around the valve stem.

3. A gate valve, embodying a. casing, a valve stem therein, a lifting nut in screw- Copies threaded engagement with said valve stem, gates carried by said lifting nut, and projections on said lifting nut and gates engaging eoinmon grooves in said casing for preventing rotation of said lifting nut and gates during rotation of said valve stem.

4. A gate valve embodying a casing, a valve stem therein, a lifting nut in screwthreaded engagement with said valve stem and formed with oppositely projecting lugs, and gates recessed in their backs to receive said lugs, the opposite surfaces of said recesses being in close relation to said lugs, whereby said gates Will be supported and lifted by said lugs during upward movement of said nut, and will be forced to their seats by said lugs during downward movement of said nut.

5. A gate valve, embodying a casing, a valve stem therein, a lifting nut in screvv threaded engagement with said valve stem and formed with oppositely projecting lugs, and gates formed with recessed abutments receiving the lugs of said lifting nut, Whereby said gates are loosely supported thereby, the ahutments of said gates and the ends of the lugs on said lifting nut engaging common grooves in said casing for preventing rotation of said lifting nut and gates during rotation of said valve stem.

6. A gate valve, embodying a casing, a valve stem therein, a lifting nut in screwthreaded engagement with said valve stem and formed with oppositely projecting lugs having reduced outer ends, and gates formed with recessei'l abutments receiving the lugs of said lifting nut, whereby said gates are loosely supported thereby, the abutments of said gates and the reduced ends of the lugs on said lifting nut engaging common grooves in said casing for preventing rotation of said lifting nut and gates during rotation of said valve stem.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

WILLIAM G. MARSH. Vi tnesses N. F. GOULD, B. M. SULLIVAN.

addressing the Commissioner of Patents,

Washington, D. 0. 

